Apart from the polar regions, hippoids can be found on beaches throughout the world. Larvae of one species have also been found in Antarctic waters, despite the lack of suitable sandy beaches in the Antarctic.[7]

Alongside hermit crabs and allies (Paguroidea), squat lobsters and allies (Galatheoidea) and the hairy stone crab (Lomis hirta, Lomisoidea), Hippoidea is one of the four groups that make up the infraorder Anomura.[8] Of the four, Hippoidea is thought to be the most basal, with the other three groups being more closely related to each other than to Hippoidea.[9]